watchdog: Automatically register device with sysreset

Add an option to automatically register watchdog devices with the
wdt_reboot driver for use with sysreset. This allows sysreset to be a
drop-in replacement for platform-specific watchdog reset code, without
needing any device tree changes.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Stefan Roese <sr@denx.de>

include/sysreset.h

@@ -133,4 +133,14 @@ void sysreset_walk_halt(enum sysreset_t type);
  */
 void reset_cpu(void);
 
+/**
+ * sysreset_register_wdt() - register a watchdog for use with sysreset
+ *
+ * This registers the given watchdog timer to be used to reset the system.
+ *
+ * @dev:	WDT device
+ * @return:	0 if OK, -errno if error
+ */
+int sysreset_register_wdt(struct udevice *dev);
+
 #endif